Bulldozer



F. H. LAMB BU LLDOZER April 9, 1935.

4 'Sheets-Sheet -1 Filed Feb. 6, 1933 o d@ l INVENToR g@ H PHNKHJHM@ W ATTORNEY n Fl H. LAMB April 9, 1935.

BULLDOZER Filed Feb. 6, 1933 4 sheets-sheet 2 ATTORNEY April 9, 1935. F, H LAMB 1,997,001

BULLDOZER Filed Feb. 6, 1935 v 4 Sheets-Sheet 5 INVENTOR //VK H. E10/v6 ATTOR N EY Patented Apr. 9, 1935 NT OFFICE nmnozan Frank H. Lamb,

Hoquiam, Wash.

Application February 6, 1933, Serial No. 655,495

17 Claims.

This invention relates to dirt moving machines,

and it has reference more particularly to motorized machines now generally known in trade as bulldozers or trailbuilders and which are designed primarily for the moving of dirt by blade action such as in grading, ditching, leveling and filling, but which are applicable to various other uses and operations with a like amount of satisfaction. f As a matter of explanation, and to give a better understanding of the novel features of the present construction, it will here be stated that the earlier types of bulldozers consisted of a rigid blade supported in front of a tractor, with means whereby the blade might be raised to dump the load or to adjust it when cutting in too deeply. Due to the construction of the conventional tractor, it has been a difficult matter to attach the bulldozer to the tractor. In some types of machines the tractor is completely encircled by the bulldozer frame which takes the pushing thrust and which is attached to the rear of the tractor at the towing hitch. In some makes, the thrust is taken by brackets attached to the track frames. In practically all makes, owing to diillculty of attachment, the bulldozer is a heavy and expensive attachment.

It is also to be pointed out that in earlier day, as well as in those present day typos` of bulldozers that are applied to tractors of the track laying types, the long distance of the blade from the center of oscillation of the tractor multiplies the up and down motion of the blade as the tractor passes over uneven ground and this necessitates constant attention, and adjustment by the operator, and at best leaves an uneven, wavy grade.

It is the principal object of the present invention to provide a novel bulldozer equipment for a tractor of the crawler or tracklaying type, that has greater dirt moving capacity, with less upkeep and better adjustment than heretofore has been available. Furthermore, to provide an improved type of bulldozing, or dirt moving machine, adapted to all kinds of dirt moving operations that may be encountered in road building, grading, filling, 'ditching or similar work, and which utilizes a tractor of the track laying type as the motive and power supplying means, and which is equipped with a blade of novel form having independent, opposite end sections; the blade also being supported from the tractor frame in a manner permitting of its being raised or lowered bodily, or tilted laterally to cause one end to be lowered and the other raised, as well as providing for independent angular adjustment of the opposite end sections for the purpose of casting to either side of a roadway or to both sides, or to retain the load therein for straight ahead movement.

It is also an object of the invention to provide a machine as above stated in which the bulldozer equipment is supported by short bracketed connections relatively close to the sprocket center, or center of oscillation of the tractor, thereby reducing to a minimum the oscillation of the blade by reason of travel on uneven roadways and also gaining advantage of the weight of the heaviest part of the tractor for crowding in the cutting blade for uprooting rocks, stumps, and for working in heavy, sticky clay or gumbo soils.

It is also an object of this invention to provide easily controlled power means for eifecting the various tilting and vertical adjustments of the blade. Also to hinge the opposite end sections of the blade to a central pivoted support for easy angular adjustment, and to provide for separate and independent angular adjustment of the 'blade sections.

Another object is to provide novel hydraulic power means for bodily raising and lowering the bulldozer equipment relative to the tractor, and to provide a separate hydraulic means on the bulldozer operable at will and while the machine is in motion for eiecting the lateral tilting adjustments of the blade.

Another feature of the invention resides in the provision of a parallel link connection between the tractor frame and blade support which effects an upward and downward adjustment of the blade without change in its vertical inclination and which provides for applying a substantial part of the weight of the tractor to the blade in crowding it into the ground for heavy work.

Other objects of the invention reside in the details of constructionl of the various parts, in their combination and mode of operation, as will hereinafter be described.

In accomplishing these and other objects, I have provided the improved details of construction, the preferred forms of which are illustrated in the accompanying drawings, wherein- Fig. 1 is a side elevation of a bulldozer mechanism embodying the present invention.

Fig. 2 is a perspective view of the'rear end, por- 50 tion of the tractor chassis or frame structure showing the supporting lugs to which the bulldozer mounting brackets are to be hingedly attached.

Fig. 3 is a perspective view of the blade mount- 55 ing and tilting bar, and the adjusting shaft associated therewith.\

Fig. 4 is a diagrammatic view of the pump and control system for the two hydraulic cylinders.

Fig. 5 is a plan or top view of the machine,-as illustrated in Fig. 1. Y

Fig. 6 is a front elevation of the blade mechanism.

Figs. '7, 8, 9 and 10 are views, in plan, illustrating various angular positions to which the blade sections may be adjusted.

Fig. 11 is a plan view of a modified form of equipment.

Fig. 12 is a side view of the same.

Referring more in detail to the drawings- In its preferred construction, the present machine utilizes a tractor of the track laying type as the moving and power supplying medium. Preferably this tractor is of that kind described and illustrated in connection with the dump body mechanism of my pending application filed February 5, 1932, under Serial No. 591,072. Such a tractor, whenVused for the present purpose, should be equipped with an engine of horsepower adequate to carry on the work to the best advantage and in addition, to furnish what power is necessary for operation of the blade adjusting means.

As herein illustrated, the tractor is designated in its entirety by reference numeral I. It has a main frame, or chassis, seen best in Figs. 5 and 11, comprising opposite side beams 2-2 and suitable cross connections as at 3, joining them when needed. At their rearward ends, the opposite side beams 2 2 are rigidly secured to a heavily built, and substantial gear case 4 within which the poW- er transmission gearing and various controls through which the tractor is driven, are housed. Extending longitudinally of the chassis, at opposite sides, are the track mounting frames 5-5. These frames have their rearward ends pivotally mounted for oscillation on the opposite ends of a substantial shaft 6 that extends transversely through the case 4 as a support for that endof the chassis. At their forward ends the track frames support the chassis through the mediacy of spring suspensions of suitable form, as designated at 'I which permits the necessary movement vertically of the track frames with respects to each other and to the main frame, required to accommodate the tracks to travel over uneven surfaces without detrimental strain on the various mountings.

Tracks 8, of continuous, flexible belt construction are mounted for travel about the frames 5-5 on Wheels 9 and .I0 at opposite ends of the frames; the wheel 9 at each side being driving sprocket for the track at that side. Between wheels 9 and I l), the lower runs of the tracks are guided by and 'operate against idler wheels carried on the frames, while the upper runs are supported byidlers I2 also mounted by the frames.

The driving sprockets 9 for the tracks are mounted at the outer ends of differential axles |4-I4 which are driven through the mediacy of transmission mechanism of a suitable nature indicated at I5 in Fig. 5, which in turn has connection throughy the main drive shaft I6, and change speed gear mechanism I'I with the vehicle engine I8 mounted at the forward end of the chassis. The transmission mechanisms I5 and II, while not illustrated, provide for the operation of the vehicle in opposite directions and at various speeds and the guiding and turning of the vehicle is accomplished by driving the. tracks at the same or at different speeds.

At the forward end of the chassis, and at one side of the engine, is a cab 20 for the operator who, from this location, through manipulation of suitable/controls, operates both the tractor and the bulldozer equipment.

The bulldozer equipment is mounted at that end of the frame which, for convenience, is

termed the rear end; this being ther end opposite the engine and operators position. This equipment is connected directly to the rear end wall 4a of the heavy gear case 4, which is a part of the chassis or frame structure, through the medium 'v of two heavily constructed brackets 2| yand22 of triangular form as seen in Fig. 5. 'I'hese brackets are substantially alike in construction and are provided at opposite sides of their base ends with hinge lugs 23 disposed between paired lugs 24 fixed on or integral with the rear end wall of the gear case and hingedly secured therein by pivot bolts 25, so as to permit of an upward and downward swinging movement of the outer ends of these brackets.

In normal use, the two brackets are disposed substantially in horizontal position, and are vertically spaced, as seen in Fig. 1, and are of substantially the same length. At their swinging ends each bracket terminates in a hinge lug and these are connected by pivot bolts 26 and 21, respectively, as in Fig. 1with upper and lower end portions of an upright channel beam 28 which is a part of the blade mounting head. This beam, as presently described, supports the blade, and is vertically movable to bodily raise or lower the blade by the upward or downward swinging action of the supporting brackets on their hinge mountings. To effect this movement of the brackets, I have fixed a lever arm 30 to the upper bracket and this extends in an upward and forward direction and is connected pivotally at its ends as at 3|, with a link 32 which, at its opposite end, is pivotally attached, as at 33, to a cross head 34 reciprocally movable in a horizontal guide 35 that is rigidly fixed upon the gear case 4 in the central longitudinal line of the vehicle. This cross head is attached to vthe outer end of a piston rod 36 which is actuated by a piston 31 in a hydraulic cylinder 38 fixed to and continuing from the forward end of the guide 35. Action of r the piston in opposite directions as presently described, effects a corresponding movement of the cross head 36 and a consequent raising or lowering of the beam 28 by reason of the swinging action of bracket 2|.

It is to be pointed out, that by reason of the parallel relation of the brackets 2| and 22 and their being substantially equal in extent, the motion produced is substantially a parallel link movement which retains the beam 28 in a vertical position for different positions of vertical adjustment, and this is important as it provides for the vertical adjustment of the blade without changing its angle of inclination relative to the ground.

Disposed along the forward face of the beam 2811s the blade mounting bar 40. This is pivotally attached at its lower end to beam .28 by a pivot pin 4| which permits the upper end of bar 40 to be swung laterally in opposite directions. The bar 40 is provided on its forward face, as seen in Fig. 3, with forwardly extending brackets 42 mounting a vertical hinge pin 43 therein, and on this pin the opposite end sections 44-44 of the blade are hingedlyl mounted. 'Ihe two blade sections are alike in construction and of equal extent. Each consists of a welded sheet metal plate suitably curved to promote a rolling action of the material pushed ahead of it,.and is equipped on its back side with suitable stlilening ribs 48 and at its inner end with mounting lugs 48 receiving the hinge pin 48. y

. The hinge pin mounting permits .of swinging adjustment of the blade lsections to various angular positions transversely ofthe tractor as is clearly shown in Figs. 1 to 10 ofthe drawings. After an adiustmenthas-been made, the blade' sections are held in set positions by bracing struts 88-.89' located at opposite sides of the tractor. lThese struts have ball and socket connections. 5I at their outer ends with the outer ends of the bladesections, and are slidably` adjustable inguides '82 mounted by ball and socket connections 88 on the endsi of thecross shaft 8 which supports the track frames. Lock bolts 54 are applied to the guides andfthrough holes provided in the struts to yretain the adjustment. Thus the entire pushing strain applied through they blade mountings is taken directly by the tractor frame and not by the' track frames or vany draw bar connection.

For lateral tilting ofthe blade, the bar 48 is swung laterally on the pivot 4i to o`ne or the other side-of thel upright beam 28. To control this movement I have mounted a hydraulic cyl-` inder rigidly on-the upper end of beam 28 and transversely of the vehicle. This cylinder contains'a piston 96 xed 'on a piston rod 61 that extends from opposite ends of the cylinder. A shifting slide 68 for the bar 49 is arranged parallel with the piston rod,l forwardly of the cylinder and is longitudinally shiftable in supports 89---69'V extending from the cylinder ends. 'Ihe rod 88 has fixed connections 18-19 at its opposite ends with the piston rod and, at its center, mounts a block 12 with a pivot pin 13 extended forwardly therefrom into a vertical slot 14 in the upper end of beam 48. movement of the piston 89 is controlled by the manipulation of a control valve mechanism, presently described, operable from the drivers position; and by an application of pressure medium lto one or the other end of the cylinder,

' the rod 81 will be actuated accordingly to adjust the lateral inclination of the blade to a desired position under control of the valve control.

To protect the hinged connections of the two blade sections 44--44' with the blade head bar 48, I provide vertical V-shaped hardened steel prow 18 rigidly ilxed to the forward ends of the brackets on the blade head bar 48. 'I'his prow forms a colter in digging and materially assists in` holding the bulldozer to a straight course in breaking up hard soils or in digging out roots and obstructions.

In connection with the hydraulic cylinder 38 for lifting or lowering the blade head, I providea hydraulic pump 89 driven by its shaft 8i from suitable power take ofi', not shown, from the main drive shaft. This pump, as disclosed, diagrammatically, in Fig. 4 is operable to pump a liquid pressure medium from one end of thelcylinder .to the other to thereby adjust the position of the pistony to raise or lower the blade head and to hold it rigidly at the adjusted positions. To give control to the piston, opposite sides of the pumpA are connected to opposite sides of a four way Ivalve housing 82 by .pipes 83 and 84 which housing, in turn, has upper and lower outlets with pipe connections 'as and to opposite ends or Reciprocal cylinder 88. -The valve casing 82 contains a four way valve plug 81 rotatably adjustable by .lever 88 to controlthe direction of ow of liquid.

Lever 881s connected by link 89 with a hand lever..

'99 adjacent the operators position. There are also pipe' connections 92 and 93 between the opposite outlets of pump 80 and opposite sides of a four way valve housing 94' which has upper and lower pipe yconnections and 98 leading to opposite ends of the cylinder 85. The valve housing 94 contains a four way plug 91 rotatable by lever 98 to control flow lof pressure medium into and from opposite endsof cylinder 8l thereby to ad just and maintain any adjustment of `the-piston for holding theblade at diiierent tilted'positions. 'I'he lever 98y has a link 99 leading to al control lever |88 adjacent the operators seat.

. In Figs. l1 and l2, I have illustrated an alternative, or modified construction applicable. to'

the tractor frame in substantially the same manby the hydraulic cylinder 38I and its associated mechanism, but `having,no angular adjustment.

'This modied construction comprises a single piece blade lill set at a right angle to the longitudinal direction of the vehicle and hingedly attached to the rear end lugs 24 of the case 4 by an upper bracket 2Ia and by apair of lower end brackets "l2-|82. The upper bracket 2Ia is attached to the base 4 as is the bracket 2l of the construction previously described and is hingedly attached at |03 to the'central upper part of the blade.. The brackets |02--I02 are attached at their inner ends to the lower sets of lugs at opposite sides of the gear vcase 4 and at their outer ends are attached as at |05 to the blade adjacent its lower edge. Up andy down action of the blade is effected exactly as in the other device by connection with the cross head 34 actuated by the pistonrod 36 of hydraulic cylinder 38.

In using the bulldozer of Figs. 1 to l0, the blade is adjusted to the desired depth by action of the hydraulic cylinder 38 under control of valve 81. For land clearing, surface leveling and grading, under some conditions both ends of the blade are set at right angles to the road. When it is desired to side cast from a ll, or to throw up a fill from ditches or sides, both ends of the blade are set at appropriate angles across the road asin Figs. 7 and 8 andsecured by the bracing' struts 50-58'. To varythe lateral inclination of the blade for ditch digging this is effected by the mechanism of the hydraulic cylinder 95 under control of valve 91. When it is desired to pushv as large a load as possible, both blade sections are set forwardly, as in Fig. 9, forming a` wide V which increases the holding capacity to a material extent.

'I'he shape of the blade, which I have adopted. also tends to roll the load toward the center instead of around the end of the blade.

When it is desired to level a crowned fill, the outer ends of the blade can be set backward from the center as in Fig. 10 forming a wide plowing V which will cast the dirt to both sides. In this position the blade may be used as a snow plow with good satisfaction.

'I'he advantages to be gained by the present construction are many. Those most apparent are: `a wide range of adjustability of the blade sections; the rigidity of the construction and the application of thrust only to the frame structure of the tractor; the short connection between the blade and tractor, which reduces blade oscillation to a minimum; the possibility of applying the greater part of the-weight of the tractor to the blade to crowd fit-into the ground; the vertical adjustment "of the blade without change inl its angle relative to the ground; the vease of Adetachment of the equipment when it is desired to use the tractor for other purposes; and the comparatively low cost of producing the equipment.

Having thus described my invention, what I claim as new therein and desire to secure by Letters Patent is- A machine of the character described comprising a tractor having a rigid iframe,l a plurality of brackets in substantially parallel, vertically spaced planes, hingedly connected at their inner ends to the frame, a blade head having pivoted supporting connections with the outer ends of the brackets, a blade adjustably mounted by the head and movable to different angular positions thereon relative to the direction of travel and means for effecting an adjustment of the brackets for changing the elevation of the blade.

2. A machine of the character described comprising a tractor having a frame structure, brackets vertically spaced and hingedly attached to the frame to extend from one end thereof and adapted for up and down swinging movement at their outer ends, blade mounting means having spaced pivotal connections with the swinging n ends of said brackets, a blade adjustably mounted on said mounting means and mechanism on the tractor operable to hingedly adjust the brackets to raise or lower the blade mounting means and for rigidly retaining an adjustment thereof.

3. A machine of the character described, comprising a tractor having a rigid frame, a pair of brackets vertically spaced, and with ends hinged- 1y attached to an end wall of the frame, an upright blade head, means pivotally connecting the outer ends of said brackets with the blade head in spaced relation corresponding substantially'to that of their inner ends, a blade mounted by said blade head and means'attached to the frame and to one of the brackets for effecting adjustment of the latter for raising or lowering the blade.

4. A machine of the character described comprising a tractor having a rigid frame, vertically spaced brackets with their inner ends hingedly attached to the said frame for movement about horizontal axes; said brackets being adapted for vertical adjustment at their outer ends, a blade head having vertically spaced pivoted connections with the outer ends of said brackets, a blade mounted by said blade head and adjustable thereon to different angular positions transversely of the tractor and means on the tractor for adjusting the brackets for raising or lowering the blade.

5. A machine ofthe character described comprising a tractor having a rigid frame structure, a pair of blade mounting brackets, vertically spaced and having their inner ends hingedly attached to the tractor frame, a blade head having spaced, pivoted connections with the outer ends of said brackets and supported through said connections, a blade adjustably attached to the head, and extending laterally to opposite sides thereof, and bracing struts extended between the ends of the blade and tractor frame.

6. A machine of the character described comprising a tractor having a rigid frame structure, upper and lower blade mounting brackets hingedly mounted on the frame to extend at one end thereof in the direction of travel, a blade mounting head having spaced pivotal connections with the outer ends of the said brackets, a blade pivotally mounted by said head and adjustable on its mounting to different angular positions transversely of the tractor, means on the tractor connected with one of said brackets for raising or lowering the blade head and for retaining its adjustxnent, and struts pivotally xed'to the outer ends of the blade and to the tractor frame at opposite sides for bracing the blade. A

7. A device as in claim 6 wherein the blade has pivotal adjustment on the head about a horizontal pivot and a vertical pivot, and wherein the struts have universal connections with the blade ends and with the tractor frame.

8. A machine of the character described, comprising a tractor having a rigid frame structure, vertically spaced blade mounting brackets with ends hingedly attached to an end of the frame at opposite sides; said brackets having their outer ends disposed in the medial longitudinal plane of the tractor, an upright blade head having correspondingly spaced pivoted connections with the outer ends of the said brackets, a blade mounted u by said head and extending laterally thereof to opposite sides of the tractor, an actuating lever arm on one of said brackets, and power mechanism mountedon the tractor and rigidly connected with the said lever arm for hingedly adjusting the bracket to raise or lower the blade head and for retaining it at different working elevations.

9. A machine of the character described comprising a frame having an end wall, a pair of brackets of triangular form, horizontally disposed and vertically spaced and having hinged connections at opposite ends of their base portions with the said end wall, the outer ends of said brackets being vertically alined and vertically movable, a

. blade he'ad pivotally connected with the outer ends of said brackets to maintain them in parallel relation, a blade on said head, a lever arm iixed to the upper bracket and extended upwardly therefrom,

a hydraulic cylinder xed on the tractor, a piston operablel therein, a piston rod, an operating connection between the rod and lever and means for controlling an application of pressure medium to the cylinder for actuating the piston.

10. The combination with a tractor of the track laying type having a frame, a cross shaft supporting the frame at one end, trackframes and tracks mounted by opposite ends of said shaft, of a bulldozer mechanism comprising upper and lower brackets hingedly attached to the said frame to extend in the direction of travel from that end supported by said shaft, to swing vertically at their outer ends, a blade pivotally connected with and functionally mounted by said brackets at their outer ends, and means fixed on the tractor frame and operatively connected with the brackets for positively adjusting the depth or elevation of the blade and providing a rigid connection between the frame and blade whereby weight of the tractor may be applied to the blade.

11. In a machine of the character described, a tractor, a blade head supported from the tractor frame at one end thereof, an upright bar pivotally attached to said head to swing thereon toward opposite sides of the tractor, a blade mounted by said bar to extend laterally of the tractor and means on the head operatively connected with the bar for effecting and retaining lateral adjustments of the bar.

12. In a machine of the character described, a tractor, a blade head supported from the tractor at one end thereof, an upright bar pivotally attached to the head for lateral swinging in opposite directions, a blade mounted by the bar and yextending transversely of the tractor, a hydraulic cylinder iixed on the head, a piston operable in the cylinder and having operative connection with the movable end of said bar, and means for controlling application of pressure medium to the cylinder for moving the piston.

13. In a machine of the character described, a tractor, a blade head supported from the tractor at one end thereof, means on the tractor for adjusting the head vertically, a bar pivotally attached at its lower end to the head to swing laterally at its upper end to opposite sides of the head, a blade mounted b'y said bar and extending transversely of the tractor, a horizontally dis-A- posed hydraulic cylinder xed on the head transversely of the tractor, a piston in the cylinder, a piston rod extended from opposite ends of the cylinder and having connection at its ends with the swinging end of said bar, and means for controlling an application of pressure medium to the cylinder to move the piston` to adjust the bar and blade accordingly.

14. In a machine of the character described, a tractor having a frame, a blade head adjacent one end of the frame, brackets hingedly attaching the head to the tractor frame for vertical adjustment, a blade mounting bar pivotally attached at its lower end to the head to swing laterally in opposite directions at its upper end, a blade mounted by said bar transversely of the tractor, a hydraulic cylinder fixed on the tractor frame including a piston and piston rod, having operative connection with the brackets to raise and lower the blade head, a hydraulic cylinder xed on the blade head and including a piston and piston rod having operative connection with the bar to swing it to different positions, and dedium to theY hydraulic cylinders to control the blade movement.

15. In a bulldozer, a vehicle frame, a blade head at one end of and vertically adjustable relative to the frame, an upright blade support pivoted on the head for lateral swinging, a blade mounted by the support to be tilted to different working positions by a lateral, swinging adjustment thereof and having a hinged connection with the support for angular adjustment relative to the direction or travel.

16. In a bulldozer, a tractor including a frame, a blade head disposed at one end of the frame, means rigidly supporting the head from the frame and whereby it may be vertically adjusted, a blade mounting bar connected pivotally at one end to the head, means for adjusting its opposite end to different lateral positions, a blade hinge pin mounted by said bar lengthwise thereof, blade sections mounted by said pin to extend laterally oi' the tractor and independently adjustable to difl'erent angular positions.

laterally of the tractor and adjustable to different angular positions, and a colter prow tlxed to the bar across the hinged connection of the blades.

FRANKH. LAMB.

of, blade sections mounted by said pin to extend 

